Cardinals manager Mike Matheny sent shivers through St. Louis earlier when he told reporters that something “developed today” with Allen Craig, who is out of tonight’s starting lineup against the Giants.

As it turns out, there’s no reason for concern.

According to B.J. Rains of FOX Sports Midwest, Cardinals GM John Mozeliak announced about an hour before first pitch Wednesday that Craig woke up with discomfort in his chest. But X-rays turned up negative and the slugger is expected to return to action for Thursday afternoon’s series-finale with San Francisco.

Craig initially felt the chest discomfort in mid-July after slamming into a railing at Cincinnati’s Great American Ball Park while chasing after a foul ball. He’s been able to play through the pain up to this point.

“The Wrench” homered twice on Tuesday and is batting .298/.362/.573 in 69 games played this year. Including the 2011 postseason, he has 32 homers and 106 RBI in his last 559 plate appearances.